Silverman B, Mirsky A E
Proc Natl Acad Sci U S A. 1973 May;70(5):1326-30. doi: 10.1073/pnas.70.5.1326.
The accessibility of DNA in chromatin to both exogenous DNA polymerase and RNA polymerase is slight when compared to isolated DNA. DNA in extracted chromatin is somewhat more accessible to these enzymes than is DNA in the chromatin of isolated nuclei; and the DNA template of chromatin is more accessible to DNA polymerase than to RNA polymerase. In these experiments we have given much attention to the technique of scintillation counting, since artifacts arising in this procedure can lead to erroneous conclusions.
与分离的DNA相比,染色质中的DNA对外源DNA聚合酶和RNA聚合酶的可及性较低。提取的染色质中的DNA比分离细胞核的染色质中的DNA对这些酶的可及性略高;而且染色质的DNA模板对DNA聚合酶的可及性比对RNA聚合酶的可及性更高。在这些实验中,我们非常关注闪烁计数技术,因为该过程中产生的假象可能导致错误的结论。